Japanese Homepage: http://www.nintendo.co.jp/3ds/afej/index.html
Think this is the 13th title of the Fire Emblem series. So far a Japanese and European release have been confirmed.
The game will be released in japan on the 19/04/2012 and sometime this year in Europe (probably Australia as well)
So far we know that the game wil have two heroes, this is one of them
Spoiler:
The game will also feature DLC. These DLC, if i understand correctly, are distributed as set, containing new episodes and maps. So you don't just by one map, but a new story.
In japan the first DLC will be available on the same date as the game and available for free until the end of May 2012.
You can find a new cel-shaded trailer on: http://www.nintendo.co.jp/3ds/afej/movie/index.html
More on Fire Emblem: Intelligent Systems' Fire Emblem World homepage (make sure to check out the sound museum)